Furnace Not Igniting? Ignitor & Flame Sensor Repair Cost
Typical market range as of May 2026 · regionalized for northern Illinois
Most homeowners
$300
When a gas furnace clicks, tries to light, runs a few seconds, then shuts off and repeats, the culprit is usually a cracked hot-surface ignitor or a dirty/failed flame sensor — both inexpensive parts. A fair repair typically runs $150–$450 all-in. The ignitor part is $15–$35 and the flame sensor $10–$30; like most HVAC repairs, you're paying for the diagnosis, trip, and labor, not the part.
Pricing this job, not hiring for it? See what the work is worth →What drives the price
Ignitor vs. flame sensor
A hot-surface ignitor replacement runs ~$150–$425 installed; a flame-sensor clean or swap is often $80–$250.
Diagnostic time
Ignition faults can mimic gas-valve, control-board, or pressure-switch problems — sorting it out takes a methodical tech.
Age of furnace
On a 10+ year furnace, techs often recommend replacing the ignitor and cleaning the flame sensor together as preventive work.
Emergency timing
A no-heat call in a January cold snap may carry after-hours pricing.
In our market — McHenry County & northern Illinois
In a northern-Illinois winter, no-heat ignition calls are the bread-and-butter repair — and they spike during the first hard freeze. A flame sensor in McHenry County is frequently a $120–$220 visit; a hot-surface ignitor, $200–$350. Replacing both on an aging furnace ahead of winter is cheap insurance.
Walk in informed
A $250 ignition repair is not a reason to replace a furnace that's otherwise sound. If a no-heat call turns into a same-night pressure pitch for a $6,000 furnace, slow down and get a second opinion.
Fair Price Guide is iHVAC's market research for informational purposes and is strictly advisory. Actual prices are set by the independent technician. iHVAC is not a party to any transaction and assumes no liability, operating with zero middleman billing or liability.
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For the tech
What this work is actually worth
Undercharging is the chronic problem for independent and side-job techs — you quote the part plus a little, forget what it really costs to show up, and train customers to expect cheap. The ranges above aren't a ceiling. Here's how to think about pricing this job so you're not working for free.
Why it's worth it
Sorting an ignition fault from a gas-valve, board, or pressure-switch problem is diagnostic skill on a safety-critical appliance. The part is cheap; being right the first time on a gas furnace is not.
Don't undercut yourself
A no-heat call in January is high-value, urgent work — don't price it like a favor. Build the after-hours reality into the number when it's after hours.
Build these into every price — not just the part:
Drive + windshield time. The hour each way isn't free. If you're not billing for getting there, you're working below your hourly.
Truck, tools, fuel. Your van, gauges, recovery machine — what they cost to own and run is overhead on every single call.
License, insurance, bond. Carrying real coverage is what separates you from the unlicensed guy. It has to be priced in, not eaten.
Callback & warranty risk. Some jobs come back. A price with zero margin for a return trip loses money on the ones that do.
Taxes & self-employment. As a 1099 independent you owe self-employment tax and your own withholding. The number you charge isn't the number you keep.
Your expertise isn't free. Knowing exactly what's wrong in five minutes is the product. An unskilled-labor rate undersells the one thing customers can't get elsewhere.
Help build the real number
The most accurate guide isn't built from national averages — it's built from what techs in your area actually charged. Contribute what you charged for this job and it feeds the local range here. It's opt-in, fully anonymized, and only ever shown as an aggregate once enough techs have contributed — never your individual price, never a price iHVAC sets, never a floor anyone has to hold. Just real market information, so the whole trade prices its work fairly.
Contribute what you chargedCommon questions
Why does my furnace try to light then shut off?
Classic flame-sensor or ignitor symptom: the furnace lights, runs a few seconds, can't confirm or sustain flame, and locks out to stay safe. It usually retries 2–3 times then quits. Both fixes are inexpensive.
Can I clean the flame sensor myself?
A sensor can sometimes be cleaned with fine abrasive, but gas appliances are unforgiving of mistakes. Given the low cost of a pro visit and the safety stakes, most homeowners shouldn't DIY furnace internals.
How long does a furnace ignitor last?
Typically 3–7 years. They're a normal wear part — a failed ignitor on an otherwise healthy furnace is a routine repair, not a sign of a dying system.
Related costs
How we research these numbers
This range is synthesized from published 2025–2026 US HVAC cost data and HVAC field knowledge, then regionalized toward northern Illinois. It's market reference — not a quote, and not a price iHVAC sets. As real techs complete jobs on iHVAC, these ranges will be backed by the actual local prices homeowners pay — the most accurate source there is.
References triangulated for this guide: